Manufacture of paper making material



Patented Nev. 24, 1931 UNITED STATES PATENT oFFicE KO WATANAJBE, OIHIGASHI-KU, NAGOYA, JAPAN MANUFACTURE OF PAPER MAKING MATERIAL NoDrawing. Application filed November 1, 1929, Serial No. 404,211, and inJapan February 23, 1929.

This invention relates to improvements in the manufacture of paper.making and has for its object to recoverpulp from old printed paper byde-inking. a

The characteristic feature of this invention is to make an emulsion ofturpentine oil, a solvent of printing ink and dryprintingink, by theaction of a suitable dispersing medium such as soap solution, and to mixthe resultant emulsion of turpentine oil with old printed paperpreliminarily treated with alkali and thereupon de-inking the same bydissolution and dispersion of ink matter on the old printed paper intothe said dispersed solvent oil.

The object of this invention is to attaln the de-inking of old printedpaper easily and completely and to recover useful paper making materialof the same grade as that of. the old paper used, by a simple andeconomical process.

Heretofore old printed paper has not been utilized as a raw material forthe recovery of high grade paper pulp on account of the difliculty ofde-inking. But, by the. im-

proved method of this .invention such old printed paper may besatisfactorily used as raw material for the same purpose, and also asuccessful utilization can be attained of waste, old printed paper,which is of great demand. I 1

The execution of this invention is as follows: To make an emulsion ofturpentine oil a solution of soap as dispersing medium is 5 made of anysort of fats or oils such as soap of sesame oil.

' To explain this more fully about 30 lbs. of such soap of sesame oil isdissolved in a proper quantity of water, this solution is then mixedwith about 25 litres of turpentine oil, the resultant mixture is thenagitated violently thus producing the emulsion of turpentine oil.

5 The next treatment 'is the tearing onbreaking up of old printed paper.For this purposea paper making kneading machine is used, andto about1,000 lbs. of old paper about 3 p proper quantity of water are poureddown into the kneading machine through respec is very small. But thesespots may be comlbs. of caustic soda solution, and a.

tive supply pipes provided at'the charging portion of the kneadingmachine. In kneading of this paper mixture old paper is greatly softenedby the. action of coexisting chemicalcaustic soda, so that the kneadingaction proceeds much easier than when kneaded with water only.

The kneaded paper mixture, which is black in colour, is discharged fromthe kneading machine, and thenpoured down into the paper making potcheror the mixing machine and now said emulsion of turpentine oil is addedto this mixture, then the entire mass is agitated by constantcirculation for about thirty minutes. potcher or the mixing machine dryprinting ink on old printed paper is completely peptized intominuteparticles, and as aresult of this the pigment contained in printing inksuch as lamp black is also completely sus- 70 pended in the dispersedsolvent oil. This dispersed mixture, therefore, contains minuteparticles of peptized ink matter so that when one scoops up and pressesthis mixture in the hands a blackish muddy liquor willbe 7 separatedfrom the mixture and a white paper fibre will be retained in the hands.

A greater part of this blackish muddyliquor, which has been completelypeptized during the agitation'in the potcher or the 50 mixing machine,is then separated from the peptized paper mixture by using an apparatussuch as centrifugal separator. The re maining fibre of paper thus gainedis then poured into the potcher or the mixing ma- 35 chine'with waterand thereafter repeatedly washed by the drum washer or poured down intoa tank having a mat stretched over the bottom and provided withagitators and in this tank the muddy liquor is to be filtered v andseparated. Inactual practice of this washing process, there rarelappears minute black spots on the washed pulp mixture even if the latterpletely removed by washing andby adding a small quantity of alkali,assaid phenomena of black spots is chiefly due to a lack of thealkalinity of he kneaded paper mixture. m Moreover this removing effectis better at- During this agitation in the I tained when a smallquantity of soap is added with the alkali. The resultant product afterwashing is completely de-inked consisting of fibre from old printedpaper;

The produced material thus gained is then made up to dry pulp by a pulpmachine or into paper by being poured directly into a beater.

I claim:

Method of manufacturing paper making material consisting in preparing anemulsion of turpentine oil, with a good solvent of printing ink and dryprinting ink, by the action I of soap solution, as a suitable dispersingmedium, then mixing the resultant emulsion of turpentine oil with 'oldprinted paper preliminarily treated with alkali and thereupon de-inkingthe old printed paper by the dissolution and dispersion into the saiddispersed solvent oil.

' In witness whereof I have hereunto set my my hand.

v KO WATANABE.

